Electrical heater



y 7, 935. w. R. DAVIES 2,000,826

ELECTRICAL HEATER Filed July 21, 1934 3 Sheets-Sheet 2 37 zz-mm May 7,1935. w. R. DAVIES 2,000,826

ELECTRICAL HEATER Filed July 21, 1934 3 Sheets-Sheet s Patented May 7,1935 I UNITED STATES PATENT OFFICE ELECTRICAL HEATER Walter R. Davies,Missoula, Mont..

Application July 21, 1934, Serial No. 738,401 2 Claims. 210-38) Thisinvention apertains to new and useful imure 1 shows the device used inconjunction with provements in electrical heating, the same being anautomobile crank case 5, and. in this connecan improvement over myco-pending application tion a shell 0 is employed to enclose the coreand Serial No. 675,629, filed June 13, 1933. heating element to protectthe oil content of the 5 The principal object of the present inventioncase 5 from reaching the heating element, the 5 is to provide a liquidheater for boilers, tanks, oil of course being inflammable. crank casesand other containers wherein the Th h ater str ti i t of an lar W t acan be Varied fIOm pp a y O housing I provided with a removable frontcover hundred watts to thre th u d y a Simple 8 and a polygonal shapedbody 9 extending from 10 manner of connecting the heati g element w itsrear wall and provided with a threaded ex- 10 the current supply.tension l0, which is hollow to form a socket for Another important bjecto! the present inv the smooth inner end portion of the threaded ditionis to provide an electrical heater involving 1 t core II. a thermostaticswitch for cutting 011 the heater This core II is provided with a pairof parallel at a predetermined temperature wherein the longitudinallyextending bores therein receiving thermostatic switch is convenientlylocated and the elongated rods z |3 provided with t pable of being m yadlllstedthreaded end portions H and I5, respectively.

Thesea d various other impqrtenb Objects and Extending diametricallyinto the core H and adv of the invention W111 become apparbeinglongitudinally spaced along the core are the em to the t 0f thefollowing specification openings or small bores 16 with which thetransthe W E verse openings 11 in the rod (2 are registrable. Figure 11s a freementry vel'hcel Secflmal It will be observed that the heatingelement [8 view through a crank case showing the heater has one enddisposed into the opening l9 and instfmed the'reonthrough the opening 20in the end of the rod (3, Flgure 2 fragmentary vertical sectional theelement being wound around in the thread view through a liquid tankshowing the heater l grooves until the roper watta e is afforded, whenInstalled therewlth' the element being exposed the remaining en d of thewire is inserted into the when in use with non-inflammable liquid. conespondlng bore l5 and passed through the Figure i 3? g g y g covercorresponding opening ll in the rod IS. The removed S .owmg e ermos 1 SWc nuts 20 on the threaded portions of the rods 12 Figureils an endelevational view of the device and '3 are adapted to be fed on thethreaded 322 31 gz gg f giigg thermostatic swltch portions and againstthe inner end of the core H Figure 5 is an enlarged fragmentary detailedso as tend to pun the rods and upwardly sectional view takensubstantially on line 5-5 m thls manner rods Serve to retam q of Figure3 of the wound heating element 18 so that it will Figure 6 an enlargedfragmentary detailed be maintained in convoluted form on the core.sectional view taken substantially on line 6-6 of Insulanon hnedpen.ings extend through the body 9 of the housing 1 and through theseFigure 3.

allned openings extend the threaded portions of l on 1 e t the cam con-40 g 7 is an e a w w o the rods I2 and i3. Binding nuts 22 and 23 areprovided on the ends of the rods l2 and I3 10- e ional view taken Figure8 is a longitudinal s ct cated in the rmsmg 10 substantially on line8--8 of Figure 13.

Figure 9 is a side elevational view of one of the As can be Flgure 3,the curfent pp y conductor rods line 24 extends through a notch 25 m theedge 45 Figure 10 is a side elevational view of the other Portloh of thehouslhg 7 and has Onebf s 00nconductor rod which also fun tions as theheating ductors 26 connected to the rod l2 while the other elementretainen conductor 21 is secured to the plate 28 which, as

Figure 11 is a side elevational view of the core. shown in Figure 6 15provided with an outstand- Figure 12 is a cross Sectional View taken ingportion 29 against which one end of the cam 50 stantially on line l2--l2of Figure 2. contact 30 rides. Numeral 3| represents a shaft Figure 13is an elevational view of the outer on which the cam 30 is eccentricallymounted, end of the heater. numeral 32 representing a pin extending fromthe Referring to the drawings wherein like numercam contact and throughthe prominence 20 and als designate like parts, it can be seen thatFigdi-electrlcpartition 33, this partition being sup- 55 ported in thehousing I by having openings therein through which the threaded portionsof the rods l2 and I3 extend and having jarnb nuts 34 on the rods I2 andI! for holding the partition firmly against the di-electric spacers orwashers 35 located on the threaded portions of the rods i2 and i 3.

The shaft 3| extends through the removable cover plate 8 and is equippedwith a knob 36. A bracket 31 secured to the partition 33 is providedwith a backwardly bent portion 38 between which and the bracket proper31, one end of the bimetal element 39 is clamped. This element forms asubstantial horse shoe as shown in Figure 3 and has a spring contact 40secured at its free end. This spring contact arm 40 has a leg portion 4|which is connected by the jumper 42 to the rod I 3.

It will be observed that normally the bimetal element 39 is contractedwith the spring contact 40 engaging the cam 30. As the device heats up,the bimetal element 39 will expand and at a predetermined temperature,the contact 40 will disengage itself from the cam 30. However, thetemperature at which this cut off takes place can be minutely regulatedby actuating the knob 36 and adjusting the cam-like structure 30.

While the foregoing specification sets forth the invention in specificterms, it is to be understood that numerous changes in the shape, size,and materials may be resorted to without departing from the spirit andscope of the invention as claimed hereinafter.

Vt hat is claimed is:

1. In a heating device of the character described comprising a core ofinsulation provided with external threads, a pair of conductor rodsextending longitudinally in the core, one of said rods being providedwith an opening at its inner end, for receiving one end of a heatingelement wound on the core, the other rod being provided with a pluralityof openings longitudinally spaced therein, diametrically disposed andlongitudinally spaced bores in the core, the openings of the lastmentioned rods being registrable with the said diametrical bores, saidlast mentioned bores being selective to receive the other end of theheating element when the openings of the last mentioned rod areregistering therewith, and means at the outer ends of the rods wherebythe rods can be fed outwardly to bind the rods to the ends of theheating element.

2. In a heating device of the character described comprising a core ofinsulation provided with external threads, 9. pair of conductor rodsextending longitudinally in the core; one of said rods being providedwith an opening at its inner end for receiving one end of a heatingelement wound on the core, the other rod being provided with a pluralityof openings longitudinally spaced therein, diametrically disposed andlongitudinally spaced bores in the core, the openings of the lastmentioned rods being registrable with the said diametrical bores, saidlast mentioned bores being selective to receive the other end of theheating element when the openings of the last mentioned rod areregistering therewith, and means at the outer ends of the rods wherebythe rods can be fed outwardly to bind the rods to the ends of theheating element, said means consisting in providing threads on the outerends of the rods and nuts engaged on the threaded portions and feedableagainst the adjacent end of the core.

WALTER R. DAvIEs.

